xref: /openbsd-src/usr.bin/mail/v7.local.c (revision f2da64fbbbf1b03f09f390ab01267c93dfd77c4c)
1 /*	$OpenBSD: v7.local.c,v 1.17 2016/07/19 06:43:27 deraadt Exp $	*/
2 /*	$NetBSD: v7.local.c,v 1.8 1997/05/13 06:15:58 mikel Exp $	*/
3 
4 /*
5  * Copyright (c) 1980, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*
34  * Mail -- a mail program
35  *
36  * Version 7
37  *
38  * Local routines that are installation dependent.
39  */
40 
41 #include "rcv.h"
42 #include <stdlib.h>
43 #include <fcntl.h>
44 #include "extern.h"
45 
46 /*
47  * Locate the user's mailbox file (ie, the place where new, unread
48  * mail is queued).
49  */
50 void
51 findmail(char *user, char *buf, int buflen)
52 {
53 	char *mbox;
54 	struct stat sb;
55 
56 	/* Ignore $MAIL if it is not owned by the invoking user */
57 	if ((mbox = getenv("MAIL")) && stat(mbox, &sb) == 0 &&
58 	    sb.st_uid != getuid() && sb.st_uid != geteuid())
59 		mbox = NULL;
60 
61 	if (mbox)
62 		(void)strlcpy(buf, mbox, buflen);
63 	else
64 		(void)snprintf(buf, buflen, "%s/%s", _PATH_MAILDIR, user);
65 }
66 
67 /*
68  * Get rid of the queued mail.
69  */
70 void
71 demail(void)
72 {
73 	int fd;
74 
75 	if (value("keep") != NULL || rm(mailname) < 0) {
76 		fd = open(mailname, O_CREAT | O_TRUNC | O_WRONLY, 0600);
77 		if (fd != -1)
78 			close(fd);
79 	}
80 }
81 
82 /*
83  * Discover user login name.
84  */
85 char *
86 username(void)
87 {
88 	char *np;
89 	uid_t uid;
90 
91 	if ((np = getenv("USER")) != NULL)
92 		return(np);
93 	if ((np = getenv("LOGNAME")) != NULL)
94 		return(np);
95 	if ((np = getname(uid = getuid())) != NULL)
96 		return(np);
97 	if ((np = getlogin()) != NULL)
98 		return(np);
99 	printf("Cannot associate a name with uid %u\n", (unsigned)uid);
100 	return(NULL);
101 }
102